Descriptive characteristics of the analytic sample (n=374)
| Mean (SD) | |||
|---|---|---|---|
| Continuous variables | Total sample | Boys | Girls |
| Age (years) | 10.9 (0.4) | 10.9 (0.4) | 10.9 (0.5) |
| Body height (cm) | 145.2 (7.2) | 144.5 (6.5) | 145.7 (7.6) |
| Body mass (kg) | 39.2 (8.6) | 37.9 (7.2) | 40.2 (9.4) |
| BMI z-score | 0.4 (1.1) | 0.4 (1.0) | 0.4 (1.1) |
| Sedentary time (min/day) | 500.8 (55.9) | 500.4 (56.7) | 501.0 (55.5) |
| Light intensity activity (min/day) | 288.1 (45.3) | 287.3 (43.8) | 288.6 (46.5) |
| MVPA (min/day) | 64.4 (22.7) | 73.9 (24.9) | 57.3 (17.9) |
| Sleep duration (min/night) | 568.3 (43.4) | 561.3 (42.4) | 573.6 (43.4) |
| Screen time score | 3.0 (1.7) | 3.3 (2.0) | 2.7 (1.4) |
| Healthy diet score | 0.04 (0.99) | 0.06 (0.97) | 0.02 (1.01) |
| Unhealthy diet score | −0.01 (0.99) | 0.12 (1.14) | −0.11 (0.84) |
| Accelerometer wake/wear time (min/day) | 853.2 (45.0) | 861.7 (44.2) | 846.9 (44.7) |
| Categorical variables* | N (%) | ||
| Sex | – | 160 (42.8) | 214 (57.2) |
| BMI status (% overweight/obese) | 107 (28.6) | 41 (25.6) | 66 (30.8) |
| Physical activity (% active) | 195 (52.1) | 111 (69.4) | 84 (39.3) |
| Screen time (% low ST) | 120 (32.1) | 44 (27.5) | 76 (35.5) |
| Sleep (% long sleep) | 151 (40.4) | 52 (32.5) | 99 (46.3) |
| Diet | |||
| Healthy | 100 (26.7) | 41 (25.6) | 59 (27.6) |
| Mixed | 174 (46.5) | 75 (46.9) | 99 (46.3) |
| Unhealthy | 100 (26.7) | 44 (27.5) | 56 (26.2) |
| SES (parental education level) | |||
| Low | 105 (28.1) | 38 (23.8) | 67 (31.3) |
| Medium | 94 (25.1) | 41 (25.6) | 53 (24.8) |
| High | 175 (46.8) | 81 (50.6) | 94 (43.9) |
*Categories based on children meeting specific criteria: overweight/obese: BMI SD > +1.0; active: ≥60 min MVPA; low ST: ≤ 2.0 h ST/day; long sleep: ≥ 10.0, 9.75 and 9.5 h sleep/night for children aged 9, 10 and 11 years, respectively. Diet: healthy: > median for healthy diet score and < median for unhealthy diet score; unhealthy: < median for healthy diet score and > median for unhealthy diet score; mixed: all other participants. SES: low: GCSEs/equivalent or less; medium: A levels/equivalent; high: university degree.
BMI, body mass index; GCSE, General Certificate of Secondary Education; MVPA, moderate-to-vigorous intensity physical activity; SES, socioeconomic status; ST, screen time.